gecko-dev/intl/locale/LocaleService.cpp
2020-02-22 00:19:35 +00:00

646 lines
19 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "LocaleService.h"
#include "mozilla/ClearOnShutdown.h"
#include "mozilla/DebugOnly.h"
#include "mozilla/Omnijar.h"
#include "mozilla/Preferences.h"
#include "mozilla/Services.h"
#include "mozilla/StaticPrefs_privacy.h"
#include "mozilla/intl/MozLocale.h"
#include "mozilla/intl/OSPreferences.h"
#include "nsDirectoryService.h"
#include "nsDirectoryServiceDefs.h"
#include "nsIObserverService.h"
#include "nsStringEnumerator.h"
#include "nsXULAppAPI.h"
#include "nsZipArchive.h"
#define INTL_SYSTEM_LOCALES_CHANGED "intl:system-locales-changed"
#define REQUESTED_LOCALES_PREF "intl.locale.requested"
#define WEB_EXPOSED_LOCALES_PREF "intl.locale.privacy.web_exposed"
static const char* kObservedPrefs[] = {REQUESTED_LOCALES_PREF,
WEB_EXPOSED_LOCALES_PREF, nullptr};
using namespace mozilla::intl::ffi;
using namespace mozilla::intl;
using namespace mozilla;
NS_IMPL_ISUPPORTS(LocaleService, mozILocaleService, nsIObserver,
nsISupportsWeakReference)
mozilla::StaticRefPtr<LocaleService> LocaleService::sInstance;
/**
* This function splits an input string by `,` delimiter, sanitizes the result
* language tags and returns them to the caller.
*/
static void SplitLocaleListStringIntoArray(nsACString& str,
nsTArray<nsCString>& aRetVal) {
if (str.Length() > 0) {
for (const nsACString& part : str.Split(',')) {
nsAutoCString locale(part);
if (LocaleService::CanonicalizeLanguageId(locale)) {
if (!aRetVal.Contains(locale)) {
aRetVal.AppendElement(locale);
}
}
}
}
}
static void ReadRequestedLocales(nsTArray<nsCString>& aRetVal) {
nsAutoCString str;
nsresult rv = Preferences::GetCString(REQUESTED_LOCALES_PREF, str);
// We handle three scenarios here:
//
// 1) The pref is not set - use default locale
// 2) The pref is set to "" - use OS locales
// 3) The pref is set to a value - parse the locale list and use it
if (NS_SUCCEEDED(rv)) {
if (str.Length() == 0) {
// If the pref string is empty, we'll take requested locales
// from the OS.
OSPreferences::GetInstance()->GetSystemLocales(aRetVal);
} else {
SplitLocaleListStringIntoArray(str, aRetVal);
}
}
// This will happen when either the pref is not set,
// or parsing of the pref didn't produce any usable
// result.
if (aRetVal.IsEmpty()) {
nsAutoCString defaultLocale;
LocaleService::GetInstance()->GetDefaultLocale(defaultLocale);
aRetVal.AppendElement(defaultLocale);
}
}
static void ReadWebExposedLocales(nsTArray<nsCString>& aRetVal) {
nsAutoCString str;
nsresult rv = Preferences::GetCString(WEB_EXPOSED_LOCALES_PREF, str);
if (NS_WARN_IF(NS_FAILED(rv)) || str.Length() == 0) {
return;
}
SplitLocaleListStringIntoArray(str, aRetVal);
}
LocaleService::LocaleService(bool aIsServer) : mIsServer(aIsServer) {}
/**
* This function performs the actual language negotiation for the API.
*
* Currently it collects the locale ID used by nsChromeRegistry and
* adds hardcoded default locale as a fallback.
*/
void LocaleService::NegotiateAppLocales(nsTArray<nsCString>& aRetVal) {
if (mIsServer) {
nsAutoCString defaultLocale;
AutoTArray<nsCString, 100> availableLocales;
AutoTArray<nsCString, 10> requestedLocales;
GetDefaultLocale(defaultLocale);
GetAvailableLocales(availableLocales);
GetRequestedLocales(requestedLocales);
NegotiateLanguages(requestedLocales, availableLocales, defaultLocale,
kLangNegStrategyFiltering, aRetVal);
}
nsAutoCString lastFallbackLocale;
GetLastFallbackLocale(lastFallbackLocale);
if (!aRetVal.Contains(lastFallbackLocale)) {
// This part is used in one of the two scenarios:
//
// a) We're in a client mode, and no locale has been set yet,
// so we need to return last fallback locale temporarily.
// b) We're in a server mode, and the last fallback locale was excluded
// when negotiating against the requested locales.
// Since we currently package it as a last fallback at build
// time, we should also add it at the end of the list at
// runtime.
aRetVal.AppendElement(lastFallbackLocale);
}
}
LocaleService* LocaleService::GetInstance() {
if (!sInstance) {
sInstance = new LocaleService(XRE_IsParentProcess());
if (sInstance->IsServer()) {
// We're going to observe for requested languages changes which come
// from prefs.
DebugOnly<nsresult> rv =
Preferences::AddWeakObservers(sInstance, kObservedPrefs);
MOZ_ASSERT(NS_SUCCEEDED(rv), "Adding observers failed.");
nsCOMPtr<nsIObserverService> obs =
mozilla::services::GetObserverService();
if (obs) {
obs->AddObserver(sInstance, INTL_SYSTEM_LOCALES_CHANGED, true);
}
}
ClearOnShutdown(&sInstance, ShutdownPhase::Shutdown);
}
return sInstance;
}
LocaleService::~LocaleService() {
if (mIsServer) {
Preferences::RemoveObservers(this, kObservedPrefs);
nsCOMPtr<nsIObserverService> obs = mozilla::services::GetObserverService();
if (obs) {
obs->RemoveObserver(this, INTL_SYSTEM_LOCALES_CHANGED);
}
}
}
void LocaleService::AssignAppLocales(const nsTArray<nsCString>& aAppLocales) {
MOZ_ASSERT(!mIsServer,
"This should only be called for LocaleService in client mode.");
mAppLocales = aAppLocales;
nsCOMPtr<nsIObserverService> obs = mozilla::services::GetObserverService();
if (obs) {
obs->NotifyObservers(nullptr, "intl:app-locales-changed", nullptr);
}
}
void LocaleService::AssignRequestedLocales(
const nsTArray<nsCString>& aRequestedLocales) {
MOZ_ASSERT(!mIsServer,
"This should only be called for LocaleService in client mode.");
mRequestedLocales = aRequestedLocales;
nsCOMPtr<nsIObserverService> obs = mozilla::services::GetObserverService();
if (obs) {
obs->NotifyObservers(nullptr, "intl:requested-locales-changed", nullptr);
}
}
void LocaleService::RequestedLocalesChanged() {
MOZ_ASSERT(mIsServer, "This should only be called in the server mode.");
nsTArray<nsCString> newLocales;
ReadRequestedLocales(newLocales);
if (mRequestedLocales != newLocales) {
mRequestedLocales = std::move(newLocales);
nsCOMPtr<nsIObserverService> obs = mozilla::services::GetObserverService();
if (obs) {
obs->NotifyObservers(nullptr, "intl:requested-locales-changed", nullptr);
}
LocalesChanged();
}
}
void LocaleService::WebExposedLocalesChanged() {
MOZ_ASSERT(mIsServer, "This should only be called in the server mode.");
nsTArray<nsCString> newLocales;
ReadWebExposedLocales(newLocales);
if (mWebExposedLocales != newLocales) {
mWebExposedLocales = std::move(newLocales);
}
}
void LocaleService::LocalesChanged() {
MOZ_ASSERT(mIsServer, "This should only be called in the server mode.");
// if mAppLocales has not been initialized yet, just return
if (mAppLocales.IsEmpty()) {
return;
}
nsTArray<nsCString> newLocales;
NegotiateAppLocales(newLocales);
if (mAppLocales != newLocales) {
mAppLocales = std::move(newLocales);
nsCOMPtr<nsIObserverService> obs = mozilla::services::GetObserverService();
if (obs) {
obs->NotifyObservers(nullptr, "intl:app-locales-changed", nullptr);
}
}
}
bool LocaleService::IsLocaleRTL(const nsACString& aLocale) {
// First, let's check if there's a manual override
// preference for directionality set.
int pref = Preferences::GetInt("intl.uidirection", -1);
if (pref >= 0) {
return (pref > 0);
}
return unic_langid_is_rtl(&aLocale);
}
bool LocaleService::IsAppLocaleRTL() {
// First, check if there is a pseudo locale `bidi` set.
nsAutoCString pseudoLocale;
if (NS_SUCCEEDED(Preferences::GetCString("intl.l10n.pseudo", pseudoLocale))) {
if (pseudoLocale.EqualsLiteral("bidi")) {
return true;
}
if (pseudoLocale.EqualsLiteral("accented")) {
return false;
}
}
nsAutoCString locale;
GetAppLocaleAsBCP47(locale);
return IsLocaleRTL(locale);
}
NS_IMETHODIMP
LocaleService::Observe(nsISupports* aSubject, const char* aTopic,
const char16_t* aData) {
MOZ_ASSERT(mIsServer, "This should only be called in the server mode.");
if (!strcmp(aTopic, INTL_SYSTEM_LOCALES_CHANGED)) {
RequestedLocalesChanged();
WebExposedLocalesChanged();
} else {
NS_ConvertUTF16toUTF8 pref(aData);
// At the moment the only thing we're observing are settings indicating
// user requested locales.
if (pref.EqualsLiteral(REQUESTED_LOCALES_PREF)) {
RequestedLocalesChanged();
} else if (pref.EqualsLiteral(WEB_EXPOSED_LOCALES_PREF)) {
WebExposedLocalesChanged();
}
}
return NS_OK;
}
bool LocaleService::LanguagesMatch(const nsACString& aRequested,
const nsACString& aAvailable) {
Locale requested = Locale(aRequested);
Locale available = Locale(aAvailable);
return requested.GetLanguage().Equals(available.GetLanguage());
}
bool LocaleService::IsServer() { return mIsServer; }
static bool GetGREFileContents(const char* aFilePath, nsCString* aOutString) {
// Look for the requested file in omnijar.
RefPtr<nsZipArchive> zip = Omnijar::GetReader(Omnijar::GRE);
if (zip) {
nsZipItemPtr<char> item(zip, aFilePath);
if (!item) {
return false;
}
aOutString->Assign(item.Buffer(), item.Length());
return true;
}
// If we didn't have an omnijar (i.e. we're running a non-packaged
// build), then look in the GRE directory.
nsCOMPtr<nsIFile> path;
if (NS_FAILED(nsDirectoryService::gService->Get(
NS_GRE_DIR, NS_GET_IID(nsIFile), getter_AddRefs(path)))) {
return false;
}
path->AppendRelativeNativePath(nsDependentCString(aFilePath));
bool result;
if (NS_FAILED(path->IsFile(&result)) || !result ||
NS_FAILED(path->IsReadable(&result)) || !result) {
return false;
}
// This is a small file, only used once, so it's not worth doing some fancy
// off-main-thread file I/O or whatever. Just read it.
FILE* fp;
if (NS_FAILED(path->OpenANSIFileDesc("r", &fp)) || !fp) {
return false;
}
fseek(fp, 0, SEEK_END);
long len = ftell(fp);
rewind(fp);
aOutString->SetLength(len);
size_t cc = fread(aOutString->BeginWriting(), 1, len, fp);
fclose(fp);
return cc == size_t(len);
}
void LocaleService::InitPackagedLocales() {
MOZ_ASSERT(mPackagedLocales.IsEmpty());
nsAutoCString localesString;
if (GetGREFileContents("res/multilocale.txt", &localesString)) {
localesString.Trim(" \t\n\r");
// This should never be empty in a correctly-built product.
MOZ_ASSERT(!localesString.IsEmpty());
SplitLocaleListStringIntoArray(localesString, mPackagedLocales);
}
// Last resort in case of broken build
if (mPackagedLocales.IsEmpty()) {
nsAutoCString defaultLocale;
GetDefaultLocale(defaultLocale);
mPackagedLocales.AppendElement(defaultLocale);
}
}
/**
* mozILocaleService methods
*/
NS_IMETHODIMP
LocaleService::GetDefaultLocale(nsACString& aRetVal) {
// We don't allow this to change during a session (it's set at build/package
// time), so we cache the result the first time we're called.
if (mDefaultLocale.IsEmpty()) {
nsAutoCString locale;
// Try to get the package locale from update.locale in omnijar. If the
// update.locale file is not found, item.len will remain 0 and we'll
// just use our hard-coded default below.
GetGREFileContents("update.locale", &locale);
locale.Trim(" \t\n\r");
// This should never be empty.
MOZ_ASSERT(!locale.IsEmpty());
if (CanonicalizeLanguageId(locale)) {
mDefaultLocale.Assign(locale);
}
// Hard-coded fallback to allow us to survive even if update.locale was
// missing/broken in some way.
if (mDefaultLocale.IsEmpty()) {
GetLastFallbackLocale(mDefaultLocale);
}
}
aRetVal = mDefaultLocale;
return NS_OK;
}
NS_IMETHODIMP
LocaleService::GetLastFallbackLocale(nsACString& aRetVal) {
aRetVal.AssignLiteral("en-US");
return NS_OK;
}
NS_IMETHODIMP
LocaleService::GetAppLocalesAsLangTags(nsTArray<nsCString>& aRetVal) {
if (mAppLocales.IsEmpty()) {
NegotiateAppLocales(mAppLocales);
}
for (uint32_t i = 0; i < mAppLocales.Length(); i++) {
nsAutoCString locale(mAppLocales[i]);
if (locale.LowerCaseEqualsASCII("ja-jp-macos")) {
aRetVal.AppendElement("ja-JP-mac");
} else {
aRetVal.AppendElement(locale);
}
}
return NS_OK;
}
NS_IMETHODIMP
LocaleService::GetAppLocalesAsBCP47(nsTArray<nsCString>& aRetVal) {
if (mAppLocales.IsEmpty()) {
NegotiateAppLocales(mAppLocales);
}
aRetVal = mAppLocales;
return NS_OK;
}
NS_IMETHODIMP
LocaleService::GetAppLocaleAsLangTag(nsACString& aRetVal) {
AutoTArray<nsCString, 32> locales;
GetAppLocalesAsLangTags(locales);
aRetVal = locales[0];
return NS_OK;
}
NS_IMETHODIMP
LocaleService::GetAppLocaleAsBCP47(nsACString& aRetVal) {
if (mAppLocales.IsEmpty()) {
NegotiateAppLocales(mAppLocales);
}
aRetVal = mAppLocales[0];
return NS_OK;
}
NS_IMETHODIMP
LocaleService::GetRegionalPrefsLocales(nsTArray<nsCString>& aRetVal) {
bool useOSLocales =
Preferences::GetBool("intl.regional_prefs.use_os_locales", false);
// If the user specified that they want to use OS Regional Preferences
// locales, try to retrieve them and use.
if (useOSLocales) {
if (NS_SUCCEEDED(
OSPreferences::GetInstance()->GetRegionalPrefsLocales(aRetVal))) {
return NS_OK;
}
// If we fail to retrieve them, return the app locales.
GetAppLocalesAsBCP47(aRetVal);
return NS_OK;
}
// Otherwise, fetch OS Regional Preferences locales and compare the first one
// to the app locale. If the language subtag matches, we can safely use
// the OS Regional Preferences locale.
//
// This facilitates scenarios such as Firefox in "en-US" and User sets
// regional prefs to "en-GB".
nsAutoCString appLocale;
AutoTArray<nsCString, 10> regionalPrefsLocales;
LocaleService::GetInstance()->GetAppLocaleAsBCP47(appLocale);
if (NS_FAILED(OSPreferences::GetInstance()->GetRegionalPrefsLocales(
regionalPrefsLocales))) {
GetAppLocalesAsBCP47(aRetVal);
return NS_OK;
}
if (LocaleService::LanguagesMatch(appLocale, regionalPrefsLocales[0])) {
aRetVal = regionalPrefsLocales;
return NS_OK;
}
// Otherwise use the app locales.
GetAppLocalesAsBCP47(aRetVal);
return NS_OK;
}
NS_IMETHODIMP
LocaleService::GetWebExposedLocales(nsTArray<nsCString>& aRetVal) {
if (StaticPrefs::privacy_spoof_english() == 2) {
aRetVal = nsTArray<nsCString>({NS_LITERAL_CSTRING("en-US")});
return NS_OK;
}
if (!mWebExposedLocales.IsEmpty()) {
aRetVal = mWebExposedLocales;
return NS_OK;
}
return GetRegionalPrefsLocales(aRetVal);
}
NS_IMETHODIMP
LocaleService::NegotiateLanguages(const nsTArray<nsCString>& aRequested,
const nsTArray<nsCString>& aAvailable,
const nsACString& aDefaultLocale,
int32_t aStrategy,
nsTArray<nsCString>& aRetVal) {
if (aStrategy < 0 || aStrategy > 2) {
return NS_ERROR_INVALID_ARG;
}
MOZ_ASSERT(
aDefaultLocale.IsEmpty() || Locale(aDefaultLocale).IsWellFormed(),
"If specified, default locale must be a well-formed BCP47 language tag.");
if (aStrategy == kLangNegStrategyLookup && aDefaultLocale.IsEmpty()) {
NS_WARNING(
"Default locale should be specified when using lookup strategy.");
}
NegotiationStrategy strategy;
switch (aStrategy) {
case kLangNegStrategyFiltering:
strategy = NegotiationStrategy::Filtering;
break;
case kLangNegStrategyMatching:
strategy = NegotiationStrategy::Matching;
break;
case kLangNegStrategyLookup:
strategy = NegotiationStrategy::Lookup;
break;
}
fluent_langneg_negotiate_languages(&aRequested, &aAvailable, &aDefaultLocale,
strategy, &aRetVal);
return NS_OK;
}
NS_IMETHODIMP
LocaleService::GetRequestedLocales(nsTArray<nsCString>& aRetVal) {
if (mRequestedLocales.IsEmpty()) {
ReadRequestedLocales(mRequestedLocales);
}
aRetVal = mRequestedLocales;
return NS_OK;
}
NS_IMETHODIMP
LocaleService::GetRequestedLocale(nsACString& aRetVal) {
if (mRequestedLocales.IsEmpty()) {
ReadRequestedLocales(mRequestedLocales);
}
if (mRequestedLocales.Length() > 0) {
aRetVal = mRequestedLocales[0];
}
return NS_OK;
}
NS_IMETHODIMP
LocaleService::SetRequestedLocales(const nsTArray<nsCString>& aRequested) {
MOZ_ASSERT(mIsServer, "This should only be called in the server mode.");
if (!mIsServer) {
return NS_ERROR_UNEXPECTED;
}
nsAutoCString str;
for (auto& req : aRequested) {
nsAutoCString locale(req);
if (!CanonicalizeLanguageId(locale)) {
NS_ERROR("Invalid language tag provided to SetRequestedLocales!");
return NS_ERROR_INVALID_ARG;
}
if (!str.IsEmpty()) {
str.AppendLiteral(",");
}
str.Append(locale);
}
Preferences::SetCString(REQUESTED_LOCALES_PREF, str);
return NS_OK;
}
NS_IMETHODIMP
LocaleService::GetAvailableLocales(nsTArray<nsCString>& aRetVal) {
MOZ_ASSERT(mIsServer, "This should only be called in the server mode.");
if (!mIsServer) {
return NS_ERROR_UNEXPECTED;
}
if (mAvailableLocales.IsEmpty()) {
// If there are no available locales set, it means that L10nRegistry
// did not register its locale pool yet. The best course of action
// is to use packaged locales until that happens.
GetPackagedLocales(mAvailableLocales);
}
aRetVal = mAvailableLocales;
return NS_OK;
}
NS_IMETHODIMP
LocaleService::GetIsAppLocaleRTL(bool* aRetVal) {
(*aRetVal) = IsAppLocaleRTL();
return NS_OK;
}
NS_IMETHODIMP
LocaleService::SetAvailableLocales(const nsTArray<nsCString>& aAvailable) {
MOZ_ASSERT(mIsServer, "This should only be called in the server mode.");
if (!mIsServer) {
return NS_ERROR_UNEXPECTED;
}
nsTArray<nsCString> newLocales;
for (auto& avail : aAvailable) {
nsAutoCString locale(avail);
if (!CanonicalizeLanguageId(locale)) {
NS_ERROR("Invalid language tag provided to SetAvailableLocales!");
return NS_ERROR_INVALID_ARG;
}
newLocales.AppendElement(locale);
}
if (newLocales != mAvailableLocales) {
mAvailableLocales = std::move(newLocales);
LocalesChanged();
}
return NS_OK;
}
NS_IMETHODIMP
LocaleService::GetPackagedLocales(nsTArray<nsCString>& aRetVal) {
if (mPackagedLocales.IsEmpty()) {
InitPackagedLocales();
}
aRetVal = mPackagedLocales;
return NS_OK;
}